Relay



0. S. FIELD June 15, 1937.

RELAY Filed May 24, 1935 2 Sheets-Sheet l INVENTOR/LZM 0. 5.

ATI ORNEY Patented June 15, 1937 UNITED STTES PAENT QFFICE RELAY Application May 24, 1933, Serial No. 672,650

16 Claims.

This invention relates to electric relays, and more particularly to the polar-neutral type of such relays.

In railway signalling systems, it is often the practice to position the contacts of a polar-neu tral relay in accordance with the condition of a remote device such as a track switch. For example, such a polar-neutral relay may be energized with either polarity of direct current over a suitable control circuit in accordance with either extreme position of a track switch and deenergized when the track switch is in an intermediate position. Various circuits depending on the position of the track switch may then be controlled in accordance with the position of the polar contacts and such circuits usually include a neutral contact of the polar-neutral relay in series with such polar contacts. It then becomes vitally important that the polar contacts respond to a reversal of polarity of energy on the relay in as much as their polar and neutral contacts may select the clearing of signals over various routes, and if some abnormal condition prevents the polar contacts from assuming a new position in response to the reversal of polarity of energy on the relay but the neutral contacts assume their energized position, a clear signal may be given over a wrong and possibly an unsafe route.

In view of the above and other considerations, it is proposed in accordance with the present invention to provide a polar-neutral relay in which the position of the polar contacts must correspond to the polarity of energization of the relay in order for the neutral contacts to assume their energized or attracted position.

Other objects, purposes and characteristic features of the present invention will appear as the description thereof progresses, during which, references will be made to the accompanying drawings, in which:-

Fig. l is a partially diagrammatic view of one form of a relay constructed in accordance with the present invention.

Fig. 2 is a partially diagrammatic view of another form of a relay also constructed in accordance with the present invention.

Referring to Fig. l of the accompanying drawings, the present relay is constructed about a magnetic structure comprising three vertical parallel legs 3, 4 and 5 connected at their upper ends by a yoke 6. The center leg is a permanent magnet, or of course may be a continuously energized electro-magnet to form north and south poles as are arbitrarily assigned to the permanent magnet 4 by the respective letters N and S.

The lower free ends of the outer legs 3 and 5 are terminated by enlarged pole pieces 1 and 8 respectively.

The outer legs 3 and 5 are provided with polar operating coils t and [B respectively which are connected in series and cumulatively arranged to cause flux to flow in either direction in the outer magnetic legs 3 and 5 according to the direction of current therein as supplied over a suitable external control circuit. The outer legs 3 and 5 are also provided with neutral coils Hand l2 respectively which are also in series and cumulatively arranged to produce a. flux in the legs 3 and 5 which either assist or oppose the flux produced by the polar operating coils 9 and I according to the position of polar contacts as will be described later in detail.

A polar armature I3 is provided in magnetic relation to the lower end of the permanent magnet 4 and cooperates with the two pole pieces 1 and 8 in a manner to be operated about a pivot M to engage the side of either pole piece I or 8 according to the polarity of energy applied to the coils 9 and H A neutral armature i is also provided which is attracted to an upper position against the pole pieces I and 8 by a corresponding energization of both the polar operating coils ii and It] and the neutral operating coils II and i2.

Suitable contacts are shown in a conventional manner as being operated by the polar and neutral armatures, and it may be here mentioned that it is contemplated that the mechanical details of the present relay as shown in both Fig. 1 and Fig. 2 may be arranged as fully described in Patent No. 1,749,331 granted to O. 55. Field, March 4, 1930. It may also be mentioned here that it has been found in practice that a substantially lesser amount of flux is required in the magnetic structure to operate the polar' armature of such a polar neutral relay than is required to operate the neutral armature, or for example, it will herein be considered that fifty percent of the total ampere turns required to operate the neutral armature will satisfactorily operate the polar armature.

In the accompanying drawings, a typical con.- trol circuit for a relay constructed in accordance with the present invention is shown as operated in accordance with the position of a track switch TS. This track switch TS is shown in the conventional manner as being power operated by a switch machine SM which switch machine SM operates contact means which are conventionally shown by the contacts I6 and I1 and are arranged in a circuit for selecting the energization of the polar operating coils 9 and In from a source of energy which may be a battery B For illustrating the operation of the relay of Fig. 1, an operating circuit has been shown as controlled by the position of a track switch TS which is power operated by a switch machine SM. A source of energy is shown at the track switch location as a battery B and contacts it and Il which are shown in the normal switch position and operable to a dotted or reverse switch position are arranged to select the direction of current in the polar operating coils 9 and id. The neutral operating coils ii and 12 are energized from another battery B located at the polarneutral relay location and with a direction of current which is selected by the position of the movable polar contacts 18 and I9.

With the track switch TS in the normal position shown, a normal direction of current in coils 9 and I0 is selected by contacts l5 and H, or that is, current from the terminal of battery 3 flows through contact iii in its normal position, downward through coil 9, upward through coil l0 and back to terminal of battery B through contacts H in its normal position. This direction of current in coils 9 and IQ produces a flux forming a south pole at the pole piece 7 and a north pole at the pole piece 8 which attracts the polar armature l3 to its normal left hand position as shown.

A normal direction of current is also selected in the neutral operating coils H and 92 by the position of contacts 18 and I9, or that is, current from the terminal of battery B flows through back contact 18, downward through coil I upward through coil l2 and back to the of battery 13 through front contact iii of the polar neutral relay. This normal direction of current in coils II and 12 produces a flux which assists or strengthens the flux produced by the normal energization of the coils 9 and I0 thereby resulting in a sufficient total flux to attract the neutral armature [5 to its upper or energized position as shown.

It will now be considered that the track switch TS is operated to its reverse position thereby shifting contacts l6 and IT to their dotted positions. The direction of current in the polar operating coils 9 and I 0 is thereby reversed, or current from terminal of battery 35 flows through contact I! in its dotted position, downward through coil I 0, upward through coil 9 and back to the terminal of battery B through contact IS in its dotted position. This reverse direction of current in coils e and IE3 obviously produces a flux forming a north pole at the pole piece 1 and a south pole at pole piece 8, but in as much as current of a normal direction is still flowing in the neutral operating coils II and I2 the flux produced thereby will obviously oppose the flux produced by the reverse direction of current in coils 9 and it].

It may be here mentioned that the polar operating coils 9 and I0 normally supply approximately seventy-five percent of the total effective ampere turns required to pick up the neutral armature [5, the remaining twenty-five percent being supplied by a corresponding energization of the neutral coils H and I2. The magnetic flux produced by coils 9 and I0 being opposed by the flux produced by coils II and I2 then results in a flow of approximately fifty percent of the normal flux in the magnetic structure of the relay, and as previously described, the polar armature [3 cperates satisfactorily on approximately fifty percent of the flux required to attract the neutral armature l5, thus allowing the polar armature E3 to shift to its reverse or right hand position.

The neutral armature i5 is obviously released from the pole faces I and 8 during a change in direction of flux in the legs 3 and 5 in as much as a momentary neutralization of the flow of flux is eiiected when the increasing value of the flux formed by the new direction of current in coils ii and IE3 reaches a value equal and opposite to the flux produced by the neutral coils H and i2, and the reduced value of flux effective to operate the polar armature i3 is not sufficient to again attract the neutral armature 15. However, a reverse direction of current in coils I! and I2 is now selected by the reverse position of contacts iii and i9, or that is, current from the terminal of battery B flows through polar contact i9 in its lower position, downward through coil i2, upward through coil H and back to the terminal of battery B through polar contact S8 in its upper position, This reverse direction of current in coils II and I2 now produces a flux: which strengthens the flux produced by coils l and Ii! thereby eiiecting a total ilow of flux which is now sufiicient to attract the neutral armature [5.

Having now described the normal response of the present relay to a reversal of current on its polar operating windings, it will be considered that, with the relay in its normal position as shown, a reversal of the track switch occurs which as previously described reverses the direction of current in the coils 9 and IE), but because of some abnormal condition, the polar armature l3 does not shift in accordance with this change in direction of current in coils 9 and Hi. The neutral armature I5 is dropped during the reversal of current in coils 9 and I!) as previously described, but the polar armature l3 remaining, in its normal position maintains the normal direction of current in the neutral operating coils H and #2, which then produces a flux opposing the flux produced by the new or reverse direction of our L rent and coils 9 and Hi.

The flux in the magnetic structure of the relay effected by the new or reverse direction of current in coils 9 and I0, will reach a value of only approximately fifty percent of the flux required to attract the neutral armature l5, and obviously, as long as the abnormal condition preventing the shifting of the polar armature i3 exists, the neutral armature l5 will not be attracted.

The circuits controlled by the present polar neutral relay which may be selected by the polar contact arrangement 20 in series with the open front contacts of the neutral armature 15 will now prevent a false or dangerous condition being set up by this out-of-correspondence between the position of the polar armature l3 and the polarity of energy applied to the polar operating coils 9 and In.

In disclosing the modified form of the present invention, a relay having substantially the same mechanical construction and controlled in substantially the same manner as described in connection with Fig. 1 has been shown in 2, and consequently, such parts of the relay in Fig. 2 which may be of identical construction to parts in Fig. l have been given like reference characters with distinctive exponents. The polar operating coils 25 and 26 and the neutral operating coils 2! and 23 are arranged in substantially the same manner as similar coils of Fig. 1, except that, in Fig. 2, the polar operating coils are arranged with substantially the same number of ampere turns as the neutral operating coils, or in other words, the energization of coils 25 and 2S alone supply insufficient flux to attract the neutral armature I but sufficient to operate the polar armature I3 and the neutral armature can only be attracted by the combined effect of theenergization of both operating coils and 2t and neutral coils 21 and 28.

The neutral operating coils 21 and 28 are selectively connected by a polar contact 29 to either of two oppositely arranged asymmetric units and 3| located at the polar-neutral relay location.

These asymmetric units 30 and SI may be conventional copper oxide rectifier units, or any other type of unit which has the characteristic of transmitting current in one direction and substantially bloclning the flow of current in the opposite direc- 20 tion.

' tery B flows through contact H3 in its normal position, downward through coil 25, upward. through coil 26 and back to the terminal of battery 13 through contact H in its normal position. This normal direction of current in coils 25 and 26 produces a flux forming a south pole at the pole piece 7 and a north pole at the pole piece 8 which attracts the polar armature I3 to its normal or left hand position, as shown.

A normal direction of current also flows in the neutral operating coils 21 and 28, or that is, current from the terminal of battery B flows through contact E8 in its normal position, downward through coil 21, upward through coil 28, through polar contact 29 in its right hand position, through the rectifying unit 3! and back to the terminal of battery B through contact il in its normal position. This normal direction of current in coils 2i and 28 produces a flux which assists or strengthens the flux produced I by the normal energization of coils 25 and 25,

thereby resulting in a sufilcient total flux to attract the neutral armature M3 to its upper or energized position, as shown.

It will now be considered that the track switch TS is operated to its reverse position, thereby shifting contacts I5 and Il to their dotted or reverse positions. The direction of current in the polar operating coils and 25 is thereby reversed, or current from the terminal of battery B flows through contact il in its dotted position,

downward through coils 2t, upward through coils 25 and back to the terminal of B through contact iii in its dotted position. This reverse direction of current in coils 25 and 26 obviously produces a flux forming a north pole at the pole piece and a south pole at pole piece 8 thereby operating the polar armature I3 to its reverse or right hand position. After the polar contact 13 has thus operated to its reverse position, a reverse direction of current then flows in the neutral operating coils 2i and 28, or current from the terminal of battery 13 flows through contact il in its dotted position, through the rectifying unit 39, through contact 29 in its left hand position, downward through coil 28, upward through coil ill and back to the terminal of battery B through contact ii in its dotted position. The neutral armature l5 having been previously released during the reversal of current in coils 25 and 28 is obviously again attracted to the pole pieces ,1- and 8 by the reverse direction of current and coils 21 and 28 which produces a flux assisting the flux produced by the reverse direction of current in coils 25 and 26.

It will now be considered that due to some abnormal condition the polar arrnature I3 did not respond to the previous reversal of current in coils 25 and 26. The neutral armature I5 is released, as previously described, during this reversal of the direction of current in coils 25 and 25, and considering that the contacts [6 and ll are now in their dotted position and the polar armature I3 is in its normal or left hand position, there will be substantially no current flowing in the neutral operating coils-21 and 2!], or that is, with the polar contact 29 in its right hand position, the neutral coils 2'! and 2B are connected to the terminal of battery B through the contact 11 in its dotted position and through the rectifying unit 3! but this rectifying unit 3| will only transmit current in the opposite direction.

It will now be obvious that both the polar operating coils and the neutral operating coils of the relay in 2 are energized as long as the position of the polar armature corresponds to the direction of current applied to the polar operating coils from the external control circuit, but if the polar armature is out of correspondence with this direction of current, the neutral operating coils are connected by a polar contact in series with a rectifying unit which will not transmit current in this direction. Consequently, the neutral armature which can be attracted only by energization of both the polar operating windings and the neutral operating windings will not be attracted when the position of the polar contact is not in accordance with the direction of current in the polar operating coils thereby serving as a check on the integrity of the operation of the polar contacts.

A polar neutral relay has thus been provided in which the position of the polar contacts must correspond to the polarity of the externally controlled energization of the relay in order for the neutral armature to assume its energized position. In other words, the neutral armature serves as a check on the response of the polar armature to a change in polarity of energization of the relay, in as much as circuits controlled in accordance with the position of such polar contacts are only effective when the neutral armature is attracted to its energized position. Two means for accomplishing the above operation have been disclosed, both of which are based on the assumption that the polar armature operates on substantially smaller amount of magnetic flux than is required to attract the neutral armature. In the first means, continuous current source of energy is employed to energize an internally controlled winding, with a polarity which is selected by the position of the polar contacts of the relay, and the neutral armature can only be attracted when this polarity corresponds to the polarity of energy of externally controlled winding, which externally controlled winding can alone operate the polarized armature. The second means, however, provides for the energization of the internally controlled winding the same control wires which energize the externally controlled winding. This second means energizes the internally controlled winding only when the position the polar contacts correspond to the polarity of energy on the externally controlled winding,

which correspondence is checked by two oppositely arranged asymmetric units.

The above rather specific description of one form of the present invention is given solely by the way of example, and is not intended, in any manner whatsoever, in a limiting sense. It is also to be understood that various modifications, adaptations and alterations may be applied to meet the requirements of practice, without in any manner departing from the spirit or scope of the present invention except as limited by the appended claims.

Having thus described my invention, what I claim is:-

1. In a relay, a first winding, a polarized armature responsive to the direction of current in said first winding, a second winding, means for select ing a direction of current in said second winding corresponding to the position of said polarized armature, and a neutral armature attractable only when the direction of current in said second winding corresponds to the direction of current in said first winding.

In a relay, a first winding, a polarized armature responsive to the direction of current in said first winding, a second winding, means for selecting a direction of current in said second winding which assists the effect of energiaation of said first winding only when the position of said polarized armature corresponds to the direction of current in said first winding, and a neutral armature attractable only by said direction of current in said second winding and energization of said first winding.

3. In a relay, a magnetic structure, a first winding on said magnetic structure, a polarized armature cooperating with said magnetic structure so as to respond to the polarity of energization of said first winding, a second winding on said magnetic structure arranged to assist the effect of energization of said first winding when the position of said polarized armature corresponds to the polarity of energization of said first winding, and a neutral armature cooperating with said magnetic structure so as to operate to an attracted position only when said second winding assists the effect or said first winding.

1. In a relay, a magnetic structure including two spaced legs, a first winding on each of said legs, a polarized armature operable toward either of said legs according to the direction of current in said first winding, a second winding on each of said legs, a neutral armature responsive to the presence of current in said first winding only when the direction of current in said second winding corresponds to the direction of current in said first winding, and means including contacts operated by said polar armature for selectively energizing said second winding.

5. In a relay, a first winding, a polarized armature responsive to the direction of current in said first winding, contact means operated by said polarized armature, a second winding, a neutral armature biased to a lower position and attractable to an upper position only by a direction of current in said second winding which corresponds to the direction of current in said first winding, and circuit means including said polarized armature contacts whereby a direction of cuu'ent is selected in said second winding which corresponds to the direction of current in said first winding when said polarized armature contacts assume a position corresponding to the direction of current in said first winding and whereby a direction of current is selected in said second winding which opposes the direction of current in said first winding when the position of said polarized armature contacts does not correspond to the direction of current in said first winding.

6. In a relay, a permanent magnet, two magnetic cores equally spaced from said permanent magnet and joined at an upper end to said permanent magnet, an operating winding on said magnetic cores, a first armature cooperating with the lower end of said permanent magnet and the lower ends of said magnetic cores in a manner to operate toward either of said cores in accordance with the direction of current in said operating winding, an auxiliary winding on said magnetic cores, a source of energy for said auxiliary winding, a second armature biased away from said magnetic cores and operable toward the lower ends of said magnetic cores only when the magnetic fiux produced by said auxiliary winding assists the magnetic flux produced by said operating winding, and means for selecting the direction of current in said auxiliary winding in accordance with the position of said first armature whereby the magnetic fiux produced by said auxiliary winding opposes the magnetic flux produced by said operating winding unless the position of said first armature is in accordance with the direction of current in said operating winding.

7. In a relay, an operating winding, a polarized armature responsive to the direction of current in said operating winding, an auxiliary winding, means for connecting said auxiliary winding in multiple with said operating winding only when the position of said polarized armature correspon ds to the direction of current in said operating winding, and a neutral armature responsive only to the presence of current in both said operating winding and said auxiliary winding.

8. In combination, a magnetic structure, a first winding on said magnetic structure, a polarized armature responsive to the direction of current in said first winding, a second Winding on said magnetic structure, a neutral armature operable to an attracted position by the energization of both said first winding and said second winding, and means including rectifiers whereby current can fiow in said second winding in one direction only when said polarized armature is in one position and in the other direction only when said polarized armature is in the other position, said rectifiers being so arranged that current cannot fiow in said second winding unless the position of said polarized armature corresponds to the direction of current in said first winding.

9. A relay comprising a core, pole pieces beneath said core, a first and a second winding on said core, a first armature responsive to the direction of current in said first winding, a second armature operable against said pole pieces only when the direction of current in said second winding is effective to assist the direction of current in said first winding, and means permitting said second winding to assist said first winding only when the position of said first armature corresponds to the direction of current in said first winding.

10. A relay comprising a first winding on a magnetic core, a first armature responsive to the energization of the first winding, a second winding on the same magnetic core, a second armature responsive only to corresponding energizations of both said first and said second windings and means permitting corresponding energizations of said first and said second windings only when said first armature has properly responded to the energization of said first winding.

11. In a polar neutral relay; in combination with a polar armature; a neutral armature; and an operating core; and two means each for producing flux of opposite directions in the core, one of said means being controlled by the polar armature so as to so far neutralize flux in the core, produced by the other means, until after the polar armature has distinctively responded to the flux in the core, as to prevent picking up of the neutral armature.

12. In a polar neutral relay in which there is an operating winding and a polar and a neutral armature, means for indicating the proper response of the polar armature to the polarity of flux produced by the winding, said means in-- cluding means for adding flux to the flux produced by the winding requiring only that the polar armature shall have properly responded to the polarity of such flux.

13. In a polar neutral relay in which there is an operating winding and a polar and a neutral armature, means for indicating the proper response of the polar armature to the polarity of flux produced by the winding, said means including means for adding flux to the flux produced by the winding only after the polar armature has properly responded to the polarity of such flux, and means for continuously neutralizing a part of the flux produced by the winding until the polar armature has responded to the polarity of such flux.

14. In a polar neutral relay in which there is an operating winding and a polar and a neutral armature, means for indicating the proper response of the polar armature to the polarity of flux produced by the winding, said means including means for adding flux to the flux produced by the winding only after the polar armature has properly responded to the polarity of such flux, and means for continuously non-affecting the flux produced by the winding until the polar armature has responded to the polarity of such flux.

15. In a relay, a permanent magnet, two magnetic cores equally spaced from said permanent magnet and joined at an upper end to said permanent magnet, an operating winding on said magnetic cores, a first armature cooperating with the lower end of said permanent magnet and the lower ends of said magnetic cores in a manner to operate toward either of said cores in accordance with the direction of current in said operating winding, an auxiliary winding on said magnetic cores, a source of energy for said auxiliary winding, a second armature biased away from said magnetic cores and operable toward the lower ends of said magnetic cores only when the magnetic flux produced by said auxiliary winding assists the magnetic flux produced by said operating winding, and means for selecting the direction of current in said auxiliary winding in accordance with the position of said armature, whereby the auxiliary winding does not produce flux to assist that produced by said operating winding, unless the position of said first armature is in accordance with the direction of current in said operating winding.

16. In a polar neutral relay in which there is a polar armature and a neutral armature, an operating winding and another winding, means controlled by the extreme positions of the polar armature for steadily supplying energy to said other winding of one or the other polarity, means for at times supplying energy to the operating winding of one or the other polarity, the neutral armature responding only to the cumulative efiects of the fluxes produced by the two windings.

OSCAR S. FIELD. 

